Flexible conduit is commonly used to transfer various fluids, such as liquids, gases, or powdered solids, and such fluid flowing flexible conduits may be used in various applications to transmit power. Reinforced rubber or flexible metal hoses are commonly used in a variety of industries to transmit fluids at various flow rates and pressures in places where rigid piping is not practical due to movement between two devices. The flexible hose portion is commonly connected to a metal or plastic end to facilitate connection to stationary, rigid piping by crimping a fitted barbed end to the hose or by use of a series of clamps. In cases where the hose is frequently removed a quick disconnect type of connection is incorporated into the hose end so the operator does not need tools to make or break the connection.
In the event a failure of the flexible hose crimp or clamps, the force of the fluid will push the hose off the barbed end and cause the hose to whip and discharge the fluid in an uncontrolled manner. Hoses that have failed in this manner have been known to cause severe injury and even death in some cases. To reduce this danger, a simple safety restraint is commonly used. The simple safety restraint for such a hose consists of a flexible cable or chain connected at one end to the hose some distance from the coupling and at the other end to a fixed portion of a rigid structure. Current designs of the simple safety restraint require a bolt or screw of suitable strength to connect the restraint to the rigid structure. For applications that use the quick disconnects, this defeats the purpose of not requiring tools. If the operator fails to connect the simple piping restraint, they have compromised a critical safety feature.
One example application for a hose restraint is with hydraulic hoses utilized with diesel engine systems on an oil and gas drill rig. The drill rig consists of multiple modules. The diesel engine-hydraulic powerpack is one such module. The base structure, the mast structure, and the pipe loading structure are other modules that the diesel engine hydraulic powerpack needs to connect to. The multiple hydraulic hoses that connect between the diesel engine powerpack and the substructure & mast have quick disconnect ends to facilitate connection without needing tools and to reduce the “rig-up” and “rig-down” time.
Because of the size of some of the hydraulic hoses, a simple safety restraint of either cable or chain is typically used to provide an additional safety measure. Hoses typically fail at the connection of the metal fitting and the rubber hose. By connecting the safety restraint from a solid frame to the hose a short distance from the rubber-metal connection, should the hose fail, it will be limited in its tendency to straighten out or whip around and strike a bystander. The common method to connect the hose restraint to the solid frame is to bolt the restraint to the frame. This method defeats the purpose of using quick disconnect hose ends which don't require tools. There is a tendency for the operator to not connect the restraint rather than use the necessary tools. One additional concern is that the operator may forget to connect one of the multitudes of hoses that interconnect the structures. Failure to connect a return hose will possibly cause pressure to build up in a sensitive component and causing it to fail. An improperly connected quick disconnect can cause a hydraulic motor housing to fail and send parts of the housing flying past a service technician or other person standing nearby.
There remains a need for a flexible hose safety restraint system having a lock that can be secured without tools, the lock having a key manually interlocked with a base, the base having a sensor that provides a control signal to a control system indicating whether the key is in the locked position, and further where the control system provides an operational interlock to prevent fluid flow in the flexible hose if the key is not in the locked position.